Railway signaling system.



.5. B. HABLUW' RAILWAY'SIGNALING SYSTEM.

APPLICATION men APR. 20. m1

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JOHN B. HARLOW, OF UPPER MONTCLAIR, NEW' JERSEY, ASSIGN'OR T0 VTESTERNELEG- TRIG COMPANY, INCORPORATED, OF NEW YORK, N. "FL, A CGBPORATION OF.NEW

YORK.

RAIL'WAY SIGNALING SYSTEM.

Specification of Letters Patent.

Patented Feb. 23, 1918.

Application filed April 20, 1917. Serial No. 163,396.

To all whom it may concern:

Be it known that 1, JOHN B. HnnLoW, a citizen of the United States,residing at Upper Montclair, in the county of Essex and State of NewJersey, have invented certain new and useful Improvements in RailwaySignaling Systems, of which the following is a full, clear, concise, andexact description.

This invention relates to railway signaling systems.

The object of this invention is to provide such a system by means ofwhich a despatcher or attendant at a central station may determine whenthe train or car enters and leaves any particular section of track.

In accordance with this invention there is provided a signaling circuitextending from a central station along a railroad track which is dividedinto sections. With at'least' some of the sections of track areassociated signaling devices which may be set for operation from thecentral station and may thereafter, by the entrance ofa train or carinto the section with which the said signal sending device isassociated, be operated to send to the central station a characteristicsignal, indicating that a train or car has entered a particular section,and may later, when the train or car passes out of that section, sendanother characteristic signal indieating that fact.

The accompanying drawing is a diagram 12 and 13 and a normally closedcontact 14:.-

The closure of contacts 12 and 13 connects a source of current 15 withthe line Wires 5 and 6. The contact 14:, in the operation of the impulserelay, opens and closes a bridge of the line wires including anon-inductive resistance 16, said bridge being openwhen contacts 12 and13 are closed, and closed when contacts 12 and 13 are open, the purposebeing to provide a low resistance discharge path for retardation coils17, 17 and 18, 18, in series with the line wires, and a condenser 19 inbridge of the line wires. The retardation coils and the condenser arefor the purpose of graduating the current impulses from the impulserelay in order that they will not cause the disagreeable thump intelephonic apparatus which may be connected with the line wires duringthe transmission of an impulse.

Located at track section B is a step-bystep selective circuit-closingdevice comprising a quick-acting magnet 25 and a slowactin ma net 26 foro aeratin the ste Din 27 & b b

and holding pawls 27 and 28, which control the movement of a ratchetwheel 29. Carried by the ratchet wheel 29 isa contact arm 30 adapted inthe movement of said ratchet wheel to engage a contact spring 31. Theselector is preferably arranged to be held in its circuit-closingposition only when current is traversing the windings of these magnets.The selector may be connected in a local circuit controlled by a relay35 in bridge of the line wires. Impulse transmitting key 7 at station Ais employed for operating the selector at track section B.

A relay 39 and an electromagnet ll are under control of the selector andare actuated when contacts 30 and 31 are in engage ment. The operationof relay 39 closes contacts 414E, a5 and 46. The electromagnet 41, uponbeing energized, attracts an armature as which carries a pawl 49. Thepawl 49 engages a ratchet wheel 50, mounted on one end of the shaft 51,upon the other end of which is mounted a contact controlling Wheel 52having a notched periphery. Engaging the notched periphery of wheel 52is a spring contact member 53, and as the shaft is rotated when thearmature 42 is attracted, a contact 5% controlled by the wheel 52 andthe member 53 is alternately closed and opened. A track relay is bridgedacross the two rails of track section B and when there is no train orcar in the section it is normally energized by current from the battery61 located at one end of the section. Armature 62, of track relay 60 istherefore normally in attracted position.

A motor 65 is under the control of relay 39 and the circuit thereof isclosed when contact 4a is closed. The motor 65 is adapted to drive ashaft 66, which carries code con .to' a different combination of currentimpulses, Likewise, the selector provided with other track sectionsshould have-the contact arm positioned difierently from those of tracksections B and C. The transmitting ,key 'Zflocate'd at central stationA, is for carenters and leavestrack section B.

:25 and 26 to ground. 7 ,sent' through the selector magnets cause thestep by-smp advancement of the ratchet the purpose of calling station B,while key 9 is used for vcalling station C. It is to be understoodthatthere should be one key for eachtrack section equipped, or there maybe one master transmitting key such as vshown in PatentNo. 1,155,640 toG. Brown,

which may be set to control the sending out of a plurality of differentcombinations of impulses.

Referring to the operation of the system, it will he assumed that theoperator at station A wishes to be advised when a train or Accordingly,he will first operate the transmitting key 7, which will intermittentlyoper-' ate, impulse relay 11 to send current impulses from source 15over the line wires 5 and6. These impulses of current over the linewires will energize relay 35, causing it toopen andclose its contact 70,included in acircuit which may be traced from the live pole of battery71 through contact of relay 35 and stepping and holding magnets wheel 29to close the contacts 30 and 31, whereupon relay '39 is operated, andelecvtromagnet 4:1 is energized over a circuit which maybe traced frombattery through contacts 30 and3lof the selector, to a point 47 whereitdivides, one portion extending through the winding ofmagnet 41 toground, g-and the other through normal contact of reilay 4L8 andthewinding or" relay39 to ground.

'Thefenergization of electromagnetdl causes the closure of contact 54,whereupon relay (ii -is operated over acircuit from battery throughmember 53, ,contact5et, armature 6:2 o'l tra'ck relay 60, contact '76thereof and the winding of relayGfito ground. The operation of relay '64attracts its armatur 63. Upon the operation of .relay 39, motor 65starts torotate, due to the closure of the following circuit ffrombattery 78 through contact 44, field winding 79 and'the arma- Theimpulses thus ture of motor 65 to ground. The rotation of motor 65causes-code wheel 67 to send a distinctive signal to the central stationA, due to the alternate closing and opening of contact 80 in a circuit,which may be traced from the lower brush of motor 65 through armature 63and contact of relay 64, contact of code wheel 67, contact of relay 39,condenser 82, line wire 5, receiver 83 at station A, line wire 6,condenser Sal, contact 46 of relay 3 9, and the upperbrush and armatureof motor 65. The source of energy for this circuit is the counterelectromotire force in the armature of motor 65. The opening and closingof this circuit causes a distinctive tone to be produced in the rcceiver83, indicating to the operator at station A that the signal sendingdevice associated with track section B has been set. This answer backcontinues so long as the selector contacts 30 and 31 are closed, andthese two contacts are closed as long as current isheld on the line, dueto the operated condition of impulse relay 11, which, in turn, remainsoperated while the contact spring of the transmittingkey 7 isinvcngagemeut with the extended raised periphery of the cam segment ofthis impulse transmitting key. When the key '7 has returned to itsnormal position, impulse relay ll, relay 35, and the selector magnets 25and 26 are deenergized, whereupon. contacts 30 and 31 are disengaged,permitting the deenergizati on of electromagnct 41 and release of relay39. The release of relay 39 disconnects the answer back circuit from theline wires and stops the motor.

Subsequent to the definergization of magizet ll'and release of relay 39,a train or car enters upon the track rails 89 of tract section B,whereupon the wheels and axles of the train or car short circuit trackrela 60, causing it to release. In releasing its armature 62, trackrelay 60 causes the operation oi": relay l8 over a circuit from batterythrough member 53, contact 54-, armature 62 and contact 59 of trackrelay 60 and the winding of relay i8 to ground. In operating, relay 48completes a locking circuit for itself which includes the left-handalternate contact thereof, and causes the operation oi relay-39 over acircuit from battery through the member 53, contact 54-, right handalter nate contact of relay 48 and the winding of relay 39 to ground.Relay 39, in operating, connects the answer back circuit to the linewires and stats themotor, and since, when track relay 60 is released,relay-6i also is released, an answer back signal is now sent to thecentral station over a circuit which maybe traced from the'lower brushof motor 65 through armature 63 and contact 9]. of relay (n, contact 8].of code wheel 68, con-- tact 45 of relay 39, condenser 82, line wire 5,receiver 83, line wire 6, condenser 84,-,

contact 46 of relay 39, and the upper brush and armature of motor 65. Aslong as the train is in the section, track relay 60 will be dee'nergizedand the characteristic answer back signal, controlled by code wheel 68,will be transmitted over the line wires to the station A. However, assoon as the train leaves the section, track relay 60 is energized,thereby causing the operation of relay 64, which, in attracting itsarmature 63, removes the contact 81, controlled by code wheel 68, fromthe answer back circuit and includes therein contact 80, controlled bycode wheel 7. It will be seen, therefore, that as soon as the trainleaves the section, the answer back signal received by the ties patcherwhich indicates that there is a train in the section, will be stoppedand another answer back signal dilii'ering in character, indicating thatthe train has left the section, will be received by the dcspatcher. Thissignal will continue as long as contact 5%, controlled by magnet a1,remains closed. To stop this answer back, the despatcher again actuatestransmitting key 7 to cause the closure of contacts 30 and 31 of theselector at the station 13, whereupon the electromagnet 4:1 is energizedto open contact 54;. As soon as the transmitting key 7 has returned toits normal position, all apparatus associated with the system will berestored to normal position.

While a plurality of batteries have been shown at the trac section, itis to be understood that this is for convenience only, and that inpractice one battery may he substituted therefor. However, track battery61 is separate and distinct from the battery which is associated withthe other apparatus.

l Vhat is claimed is:

1. A railway signaling system compris ing a railroad track divided intosections, a central receiving station, a line circuit extending fromsaid station along the track, a signal sending device associated withone track section, means controlled over the line circuit for settingthe signal sending device, means controlled by the entrance of a traininto the section for causing the operation of the signal sending deviceto send a characteristic signal to the central receiving station, andmeans responsive to the passage of the train out of the section foraltering the signal transmitted to the central receiving station.

2. A railway signaling system comprising a railroad track divided intosections, a central receiving station, a line circuit extending fromsaid station along the track, a signal sending device associated with atrack section apparatus at this track section con station.

A railway signaling system comprising a railroad track divided intosections, a central receiving station, a line circuit extending fromsaid station along the track, an answer back circuit at the one section,a source of tone signaling current in the an swer back circuit,apparatus at this track section controlled from the central receivingstation, means controlled by the entrance oi a train into the sectionand cooperating with the apparatus for connecting the answer backcircuit with the line circuit, a circuit interrupting device included inthe answerback circuit upon the entrance of a train into the section, asecond circuit interrupting device, and means responsive to the passingof a train out of the section to remove the first from and to includethe second circuit interrupting device in the an swer back circuit.

4;. A railway signaling system comprising a railroad track divided intosections, a central receiving station, a line circuit extending fromsaid station along the track, a signal sending device at each of aplurality of sections, control apparatus at each of a plurality ofsections selectively set from the central receiving station, a trackrelay actuated by the entrance of a train in a particular section andcooperating with the previously set control apparatus to cause theoperation of the signal sending device, a coditying device brought intocooperative relation with the signal sending device an answer backcircuit at one section, control switching apparatus thereat actuatedunder control of the central station, a source of tone signaling currentfor the answer back circuit, a track relay actuated upon the entrance ofa train in the section, a second relay energized upon the actuation ofthe track relay and locked up under controlof the switching apparatus,and another relay operating upon the energization of the second relay toconnect the answer back circuit with the line circuit.

6. A railway signaling system comprising a rallroad track divlded intosectlons, a central receiving station, a line circuit extendoperatingupon-the .energization of the second relay to connect the answer :backcircuit with the line circuit, a codifying device, and a relay,responsive to the passage of the train rout of the section for includingthe ,codifying device in the answer back circuit.

7 7. A railway signaling system comprising a railroad track divided intosections, a central receiving station, a line circuit extending fromsaid station along said track, a signal sending device at each of aplurality of the sections, a relay adapted when oper ated to connect thesignal sending device to the line circuit, a control relay adapted whenoperated to actuate the first mentioned relay, an operating circuit forthe control relay open attvvo ,points, a selectively operated devicecontrolled over the line circuit from the receiving station for closingthe operating circuit at one point, and a track relay actuated upon theentrance of a train into the section toclose the operating circuit at1ts other point.

8. A railway signaling system comprising a railroad track divided intosections, a centralreeeiving stat on, a line c1rcu1t extending from saidstation along said track, a

signal sending device at veach of a plurality of the sections, a relayadapted when oper ated to connect the signal sending device to the linecircuit, a control relay adapted when dication is transmitted over theline circuit.

.9. A railway signaling system comprising a railroad track divided intosections, a central receiving station, a line circuit extending fromsaid station along the track, an answer back circuit at each of aplurality of sections, a source of tone signaling current for the answerback circuit, a relay adapted when energized to connect the answer backcircuit with the line circuit, a control relay adapted when operated tocause the energization of the first mentioned relay, an operatingcircuit for the control relay open at two points, a selectively operateddevice controlled over the line circuit from the central station forclosing the operating circuit at one point, a track controlled deviceactuated upon the entrance of a train into the section to close theoperating circuit at its other point, a plurality of codifying devices,and a switching device controlled by the track controlled device forincluding one of the codifying devices in the answer back circuit when atrain is in the section and for including the other of the codifyingdevices .in the answer back circuit upon the passage of a train out ofthe section.

In witness whereof, I hereunto subscribe my name this 19th day of April,A. D. 1917.

JOHN B. HARLOW.

Cepies'of this patent may be obtained for'five cents each, by addressingthe Commissioner of Patents.

: Washington, D. G.

